1. Field of the Invention
The invention relates to pressure cookers.
2. Description of the Prior Art
The invention relates more particularly to a pressure cooker lid that remains securely locked in position whenever pressure inside the cooker is above a predetermined pressure. This prevents the lid being removed or becoming loose inadvertently until the inside pressure is below a safe level. Several proposals for locking cooker pressure lids are already known. For example, in U.S. Pat. No. 5,678,721 a lid is held closed by a locking valve that prevents release of radially slidable clamp jaws until pressure inside the cooker falls to a safe level. In U.S. Pat. No. 5,678,721 the locking valve may fail in its operation or its plunger may fail mechanically so that the jaws are then free to move and the lid to open.